Floating grease seal



Patented July 3, 1945 FLOATING GREASE SEAL John B. Sperry, Aurora, lll.,axignor to The American Well Works, a corporation of IllinoisApplication June 13, 1942, Serial No. 446,950

Claims.

One of the most ditficult problems in connection with rotarydistributors for sewage and water treatment is in connection with therotary seal. The rotary distributor comprises two oppositely extendingpipes, each provided with oritices along its length andwhich rotatetogether about a central point so as'to sprinkle the liquid beingtreated uniformly over a large area. Obviously, there must be a rotaryseal somewhere between the rotating structure and the fixed supply pipefor delivering the liquid to the rotating structure.

According to conventional practice, the supply pipe extends upwardlythrough the center of the filter bed to be sprinkled and a manifoldrotates at the top of the supply pipe or column, being carried bysuitable bearings and having the oppositely disposed distributor arms orpipes communicating therewith and carried thereby. Before the presentinvention, the most satisfactory seals heretofore have comprised mercuryseals. For this purpose an annular well was provided around the supplycolumn and partially filled with mercury and the manifold was providedwith a skirt which dips into the mercury. The hydrostatic pressure ofthe liquid being treated would force the mercury somewhat higher on theoutside than on the inside, but the mercury is heavy enough so that,unless something goes wrong, it stays within the well and eifectuatesthe seal. Sometimes, however. an excess of hydrostatic pressure causes ablowout of the mercury seal, blowing the mercury out of the well. Thiswould render the seal ineffective, with the result that the rotarydistributor would cease to function properly. Furthermore, the mercuryis expensive and the seal, therefore, has represented a major expenseboth in initial cost and in maintenance. tween the manifold and thesupply column, being located on the outside of the well. This madeaccess to the well difficult and also subjected the bearing to injury inthe case of a blowout.

According to the present invention. the mercury is dispensed with. thepossibility of blowouts is completely removed. and the bearing islocated in a protected position within the well. All of this isaccomplished by providing a seal of floating oil, the floating oil beingprevented from being blown out not by its own weight, but by flexiblesealing rings. The skirt of the manifold extends into the well and intoa body of water near the bottom of the well. On the outside of the ringa pool of oil is provided and, since oil is lighter than water, itfloats on the water and,

A bearing was usually provided behence, stays up above the bottom of theskirt. The flexible sealing ring and the bearing are positioned in thepool of oil and are lubricated thereby and, in addition, an upperflexible sealing ring is preferably positioned above the bearing forreasons which are brought out below. Of course, this upper ring is alsolubricated by the oil. Additional objects and advantages of theinvention will'be apparent from the following description and from thedrawing, which is a vertical cross-sectional view of a rotarydistributor embodying the present invention, the distributor arms beingbroken away. A preferred form of the invention has bee chosen forillustration and description, in compliance with Section 4888 of theRevised Statutes, but persons skilled in the art will readily perceiveother means for accomplishing the same results, and the claims aretherefore to be construed as broadly as possible, consistent with theprior art.

The rotary distributor chosen for illustration .includes a main supportII and a manifold l2 which rotates with respect thereto. The support Hcomprises a conduit of large cross-section through which water, sewageor other liquid to be treated is supplied to the manifold H. Themanifold l2 carries distributor arms l3 which are 0 provided along theirlength with a plurality of orifices, not shown, for sprinkling theliquid being treated on a filter bed at the center of which the mainsupport I I is located. According to conventional practice, each orificeis probably provided with a spreader plate for spraying out the liquid.The manifold l2 and its arms l3 may be rotated by reaction of the waterbeing forced out of the orifices or off of the spreader plates or it maybe rotated by a motor. In any event, it will be provided with a suitablemain bearing. In the illustrated form. the bearing comprises aball-bearing assembl M, the inner ring of whicn is carried by a verticalstub shaft l5 carried by three legs I! which are in turn carried by themain support II. The shaft l6, legs I! and support It may comprise anintegral casting.

A plurality of braces iii are preferably provided for supporting theouter portions of the distributor arms. The manifold may be constructedto provide an air cushion [9 in the upperportion thereof so that theliquid level would be at about the line 2|, .even though the hydrostaticpressure might be considerably more than would be indicated by thisheight. The bearing assembly I4 is preferably protected by a pair ofsealing rings 22 and 23, the upper ring being cupped upwardly to retainthe grease and the lower sealing ring being cupped downwardly to excludewater from the grease.

Rotary seal The sealing of the running joint between the manifold l2 andthe supply column II is a more serious problem. This is partly becauseof the large diameter of the main column and partly because of thecomplete absence of a dome such as the top of manifold 12 which lendsitself to the formation of a completely sealed air pocket l9, which issealed not only by the sealing rings 22 and 23, but also by the plate24, gaskets being provided for this plate and also below top 25 of themanifold. Furthermore. the air pocket I! is replenished with airfrequently because every time the rotary distributor is shut off evenmomentarily the water level drops approximately to the bottom of thedistributor arms I! and, hence air can get into the pocket I! throughthe distributor arms It.

To effectuate the running seal in question between the manifold l2 andthe supply column H, the manifold i2 is provided with a skirt whichprojects into an annular well 21 formed by the inner wall 28 which isthe main wall of the supply standard H, and an outer wall 25 which isformed integrally with the column Ii.

Water flows down through the annular space II to form a pool of water inthe bottom of the well 21. It is prevented from rising more thanslightly above the bottom of skirt 2! by a ring of grease or oil 32which forms a pool floating on the water 33.

The skirt 24 is preferably machined to form a bearing surface it thereonand a bearing ring 31 is positioned to engage this bearing surface. Thebearing ring 31 not only has a smooth running fit with the bearing 38,but it fits smoothly within the upper portion of the wall 29. It may fitfairly tightly against this wall, but it need not be tight enough toprevent its rotation as rotation of the bearing ring 31 may be preventedby a bearing lock 38 which may be threaded to the wall 2! and providedwith a lock. nut.

A pressure fitting 41 is also preferably secured to the wall 29 so thatoil may be supplied under pressure to the chamber 42 on the outside ofthe bearing ring. The pressure fitting 4! will,

of course, have the conventional check valve incorporated therein. Thebearing ring 31 preferably has passages, such as the openings 43,through its upper and lower flanges and in any event will be providedwith some passages through which 011 can get to the bearing surfaces.The bearing surfaces may be provided with helical oil grooves, ifdesired.

Seal rings 46 and 41 are preferably provided above and below the bearingring 36. These seal rings may be identical and similar to conventionalseal rings. Each may comprise a metallic outer ring l1. having a drivenfit with the wall 29 so that leakage will be prevented therebetween anda flexible sealing ring 48 made of leather or other oil resistentmaterial clamped in a tight leak-proof manner to the ring 41. Theseflexible rings are preferably cupped downwardly to resist upwardpressure, the cupped portion being reliably urged against the skirt 26by a coil spring 49 therearound.

If oil is supplied through fitting 4| with sufficient pressure, it willooze through the lower sealing ring 41, since these rings resist upwardpressure much more efiectively than downward pressure. Supplying oilthrough the nipple 4| will, therefore, ordinarily be all that isnecessary to maintain the supply of oil both for lubricating the bearingring 31 and for maintaining the floating pool of oil 32. However,another pressure fitting 5| may be provided below the lower ring 41 and,if desired, a pipe plug 52 may also be provided below the lower ring 41to serve as an air vent when desired or for pouring in a supply of oilinitially. It is also desirable to provide a pet cook 53 through whichthe level of the pool of oil 32 may be checked. Of course, if desired, agauge could be provided with its glass tube communicating at itsopposite ends above and below the intended water-oil level. A drain andsediment removing plug 54 is preferably provided at the bottom of thewell 21.

The oil used for the seal is preferably a fairly heavy (viscous) oil,such as S. A. E. 60 or 70. A light grease could also be used. In fact,any floating lubricant could be used, if it lubricated the bearingproperly and did not appreciably ooze through the mechanical seals(rings 46 and 41).

From the foregoing, it is seen that a very satisfactory rotary seal andbearing structur is provided. The portion of the oil pool 32 below thelower ring 41 serves as an oil lock for preventing any oil from reachingthe ring 41. It also lubricates the ring so that skirt 26 rotatestherewithin with very little friction. The ring 41 and pool 32 togethergive the bearing 31 absolute protection against the possibility of waterbeing forced into the bearing by the hydrostatic pres? sure on thewater. Even if the lower ring 41 should develop a defect, the upper ring41, together with the oil 32 would prevent the water from reaching thebearing 31, since the oil would not be permitted to escape and the watercould not rise as long as the oil were retained. The

upper ring 41 also protects the bearing from dirt and moisture, althoughthere is no pressure downwardly on it and it is in a sheltered position,so that ordinarily no moisture falls on the upper ring and very littledust. By locating the bearing within the well 21 and specifically withinthe oil pool therein, it is thus thoroughly protected from harmfulsubstances. Furthermore, it permits use of the skirt 26 for one bearingmember instead of necessitating extra parts.

I claim:

1. A rotary seal between first and second conduit members, one of whichrotates with respect to the other, including an annular well formed bythe first member around the passage therethrough and open at its top, askirt carried by the second member and extending into said well, a poolof oil outside of said skirt within said well and floating on water atthe bottom of the well, and a mechanical sealing ring adapted to retainsaid oil within the well against the upward hydrostatic pressure exertedthereon by the water as water is supplied to the rotary member throughthe other member.

2. A rotary seal between a vertically disposed member and anothermember, one of which is adapted to rotate with respect to the other andto form with it a passage for a given fluid under pressure, comprising asealing ring, including a flexible cupped member sealing the spacebetween the rotary and stationary members and having a running fit withone of them, said sealing ring including a material deleteriouslyaffected by said fluid and a pool of a second fluid, which does notdeleteriously affect said seal ring and which lubricates said seal ring,positioned between the seal ring and the given fluid, and floating onthe given fluid.

3. A rotary seal between a vertically disposed member and anothermember, one of which is adapted to rotate with respect to the other andto form with it a passage for a given fluid under pressure, comprising asealing ring including a flexible cupped member sealing the spacebetween the rotary and stationary members and having a running flt withone of them, said sealing ring including a material deleteriouslyaffected by said fluid and a pool of a second fluid, which does notdeleteriously affect said seal ring and which lubricates said seal ring.positioned between the seal ring and the given fluid,

4. A running seal including a first and a second member communicatingwith each other: one of which forms a conduit, and one of which isadapted to move with respect to the other, a well formed around one ofthe members and open at its upper end, a skirt formed on the othermember and projecting downwardly into the well. a ring of lubricant inthe well on the outside of the skirt and adapted to float on the fluidto be carried by the conduit, and a flexible seal in the well around theskirt cupped in a direction to resist the pressure differential betweenthe conduit and the atmosphere and exposed to said lubricant in thedirection toward which it is cupped.

5. A running seal including a first and a second member communicatingwith each other: one of which forms a conduit, and one of which isadapted to move with respect to the other. a well formed around one ofthe members and open at its upper end. a skirt formed on the othermember and projecting downwardly into the well. a ring of lubricant inthe well on the utside of the skirt and adapted to float on the fluid tobe carried by the conduit, a flexible seal in the well around the skirtcupped in a direction to resist the pressure differential betwen theconduit and the atmosphere and exposed to said lubricant in thedirection toward which it is cupped, and a bearing in the lubricantbetween the outside of the skirt and the wall of the well.

6. A running seal including a first and a second member communicatingwith each other: one of which forms a conduit. and one of which isadapted to move with respect to the other. a well formed around one of-the members and open at its upper end. a skirt formed on the othermemher and projecting downwardly into the wellv a rine of lubricant inthe well on the outside of the skirt and adapted to float on the fluidto be carried by the conduit. and a mechanical seal n rin adapted toretain said lubricant within the well against the pressure differentialbetween the conduit and the atmosphere.

'7. A running seal including a first and a second member communicatingwith each other: one of which forms a conduit, and one of which isadapted to move with respect to the other, a well formed around one oithe members and open at its upper end, a skirt formed on the othermember and projecting downwardly into the well, a ring of lubricant inthe well on the outside of the skirt and adapted to float on the fluidto be carried by the conduit, and a mechanical sealing ring adapted toretain said lubricant within the well against the pressure differentialbetween the conduit and the atmosphere, said mechanical sealing ringbeing more resistant to the flow of fluid in the direction it is urgedby said pressure differential than in the other direction.

8. A running seal including a first and a second member communicatingwith each other: one of which forms a conduit, and one of which isadapted to move with respect to the other, a well formed around one ofthe members and open at its upper end, a skirt formed on the othermember and projecting downwardly into the well, a ring of lubricant inthe well on the outside of the skirt and adapted to float on the fluidto be carried by the conduit, and a mechanical sealing ring adapted toretain said lubricant within the well against the pressure differentialbetween the conduit and the atmosphere, a second ring spaced outwardlytoward the atmosphere from said ring, and means for introducing thelubricant under pressure between said rings; the outer ring being moreresistant to the flow of lubricant outwardly than is the inner ring tothe flow of lubricant inwardly.

9. A running seal including a first and a second member communicatingwith each other; one of which forms a conduit, and one of which isadapted to move with respect to the other, a well formed around one ofthe members and open at 85 its upper end, a skirt formed on the othermember and projecting downwardly into the well, a ring of lubricant inthe well on the outside of the skirt and adapted to float on the fluidto be carried by the conduit, and a mechanical sealing ring adapted toretain said lubricant within the well against the pressure differentialbetween the conduit and the atmosphere, and a second ring of likecharacteristics spaced outwardly toward the atmosphere from said ring,and means for introducing the lubricant under pressure between saidrings, a bearing in said space and exposed to the grease therein; theouter ring being more resistant to the flow of lubricant outwardly thanis the inner ring to the flow of lubricant inwardly.

10. A rotaryseal between a vertically disposed member and anothermember, one of which isadapted to rotate with respect to the other andto form with it a passage for a given fluid under pressure, comprising asealing ring including a flexible cupped member sealing the spacebetween the rotary and stationary members and having a running fit withone of them, said sealing ring including a material deleteriouslyaffected by matter carried by said fluidfand a pool of fluidsubstantially free from said matter, which does not deleteriously affectsaid seal ring and which lubricates said running flt, positioned betweenthe seal ring and the fluid carrying said matter.

JOHN B. SPEBRY.

